Nordic ski boots and bindings for skating have existed since at least 1989. Generally, the features included in the boots and bindings are provided mainly to enable the boot to precisely control the ski. These features can include having one or more large ridges or grooves running the length of the ski, and/or a horizontal metal bar under the toe. The soles and cuffs of the boots are typically very stiff, so as to allow only one plane of motion in the ankle in a very limited range of motion (plantar flexion/dorsiflexion).
The quest to give the skier more control of the ski via the boot has also led to boots with very narrow toe boxes, and to the “Pilot” boot-binding systems. Other than the Pilot systems, there are two basic boot-binding types: the “profil” (one large wide groove runs the length of the sole of the boot and fits like puzzle pieces with a similar raised part on the binding); and the “NNN” (two smaller grooves on the sole of the boot fit like puzzle pieces with a similar raised pattern on the binding). Nordic ski boots are generally made of rigid materials, and are rigid in many locations on various boots, especially skate boots. Many of these Nordic boots attempt to imitate the control of the ski of Alpine ski technology, by imitating some of the features of Alpine ski boots, particularly regarding stiffness.
Each Nordic boot company has a “typical” proportion, which runs throughout their boots. Boots are generally made in skate, classic, and combi/pursuit versions. Nordic skiers complain of uncomfortable feet from too-tight toe boxes and poorly fitting boots. Some people who would like to Nordic ski do not, because they cannot find a boot which they are comfortable wearing.
Existing Nordic ski boots contribute to stresses which can lead to overuse injuries. In particular, there has also been a steep rise in the incidence of chronic exertional compartment syndrome in Nordic ski racers, particularly in Juniors (19 and younger) and in sponsored (professional) athletes. This syndrome is referred to by Nordic skiers as “compartment syndrome.” It is a serious overuse injury of the lower leg in which a buildup of fluid and inflammation fills one or more of the fascial compartments of the lower leg, to the extent that the compartment is completely full and experiences a significant amount of pressure. The fluid cannot escape because the blood and lymph vessels are compressed and unable to function. In many cases, skiers with compartment syndrome require surgery, often multiple times, with a long recovery period following each surgery. There has been very little knowledge of what to do about compartment syndrome, particularly for prevention.
What is needed, therefore, is a Nordic ski boot which provides excellent ski control while at the same time significantly reducing the risk of compartment syndrome.